math.h: Provide definition of math_errhandling

https://en.cppreference.com/w/c/numeric/math/math_errhandling.html

Signed-off-by: Luca Bacci <luca.bacci@outlook.com>
Co-authored-by: LIU Hao <lh_mouse@126.com>
Signed-off-by: LIU Hao <lh_mouse@126.com>
diff --git a/mingw-w64-headers/crt/math.h b/mingw-w64-headers/crt/math.h
index 65c41cd..b5ddf94 100644
--- a/mingw-w64-headers/crt/math.h
+++ b/mingw-w64-headers/crt/math.h
@@ -168,6 +168,17 @@
   #define __setusermatherr __mingw_setusermatherr
 #endif
 
+#define MATH_ERRNO 1
+#define MATH_ERREXCEPT 2
+
+#if defined __FAST_MATH__  /* no error handling.  */
+# define math_errhandling  0
+#elif defined __NO_MATH_ERRNO__  /* errno is not used; only exceptions.  */
+# define math_errhandling  MATH_ERREXCEPT
+#else
+# define math_errhandling  (MATH_ERRNO | MATH_ERREXCEPT)
+#endif
+
   double __cdecl sin(double _X);
   double __cdecl cos(double _X);
   double __cdecl tan(double _X);